pthread_mutex_consistent_np Syntax

Call pthread_mutex_consistent_np() while holding
the mutex acquired by a previous call to pthread_mutex_lock().

The critical section protected by the mutex might have been left in
an inconsistent state by a failed owner. In this case, make the mutex consistent
only if you can make the critical section protected by the mutex consistent.

Calls to pthread_mutex_lock(), pthread_mutex_unlock() , and pthread_mutex_trylock() for a consistent
mutex behave in the normal manner.

The behavior of pthread_mutex_consistent_np() for
a mutex that is not inconsistent, or is not held, is
undefined.